LONDON — During a week of bluebird skies and Mediterranean temperatures, when sunbathers thronged parks and cars poured back onto streets, one sound has been notably absent in London: the wail of ambulance sirens.

Britain’s capital had only a handful of deaths from the coronavirus in the last week. Even the number of new cases dwindled to barely a dozen a day, suggesting that the virus, which so recently coursed through a ghostly city, has ebbed, leaving people relieved but unsure of exactly how much to relax.

The same sharp declines have occurred in other European capitals — from Paris and Rome to Berlin and Madrid — and across the continent, they are stirring similar feelings of ambivalence as political leaders balance the pressure to reopen their economies with worries that doing so could ignite another round of the contagion.

“My fear is that this good news could lead to complacency, which could lead to a second wave,” London’s mayor, Sadiq Khan, said this week.

The reasons for the declining numbers vary from city to city. Some, like London and Paris, were struck by the virus early on and have smothered its spread with two months of suffocating lockdowns. Others, like Rome and Berlin, were less hard hit than other cities in their countries. Madrid, though also reporting a decline in new cases and deaths, is still the epicenter of Spain’s outbreak.

What unites these cities is that they are home to the politicians who must decide how quickly to ease national social distancing measures. They are also the headquarters for news outlets that cover the pandemic, as well as popular tourist meccas and, in several cases, the economic drivers for their countries.

The growing pressure for regular life to resume complicates the debate over how quickly leaders should lift lockdowns, especially when other parts of their countries are still in the teeth of the epidemic.

In Britain, officials in Scotland and northern England are balking at Prime Minister Boris Johnson’s plan to reopen schools and some shops in early June. The northwest, which includes the city of Manchester, now has more coronavirus patients in hospitals than London does.

“The surprisingly permissive package might well be right for the southeast, given the fall in cases there,” Andy Burnham, a Labour Party politician who is mayor of Greater Manchester, wrote in a recent column in the Guardian. “But my gut feeling told me it was too soon for the north.”

At the same time, he and other officials worry that if the government staggers the reopening, putting London first, it will handicap the northern cities economically. That would deepen a divide between north and south that Mr. Johnson’s Conservative Party promised to bridge after its general election victory last December.

If anything, the pandemic has further exposed that divide. London’s reduced infection rate in part reflects its services-intensive economy, which enabled bankers, lawyers and other professionals to work from home. In the industrial north, factory workers have continued to clock in, exposing them to the virus.

“The sensible approach would be to start lifting the lockdown, depending on how the virus is spreading, in different parts of the country,” said Paul Swinney, the director of policy and research at the Center for Cities, a research group in London.

So far, though, Mr. Johnson has vowed that Britain will emerge from the lockdown in unison. With the economy gasping, he is under intense pressure from members of his party to ease restrictions, particularly in Greater London, which accounts for roughly 20 percent of Britain’s economic output.

“The politics of it are so difficult, particularly with northern mayors because of the leveling-up agenda,” said Tony Travers, a professor of politics at the London School of Economics. “Boris Johnson doesn’t worry about Sadiq Khan in London, but he does worry about Andy Burnham in Manchester.”

In London, signs of normalcy are widespread. Sidewalks in the Brixton neighborhood were full of pedestrians this week as workers began setting up well-spaced tables at an outdoor cafe. A pub in Stoke Newington served takeout beer. In Hampstead Heath, hundreds of people came out to sun themselves, prompting complaints about litter.

Nearly 6,000 people have died in London during the epidemic. But in the last week, hospitals reported only nine deaths on Monday, seven on Tuesday and two on Wednesday. On Monday, there were no new reported cases for a 24-hour period.

“Members of the public are starting to think, ‘Why am I still locked down when I’m living in a city where the chances of catching Covid-19 are lower than being run over by a car in the street?’” Mr. Travers said.

In Paris, where new infections have plunged from more than 1,000 a day to a couple of dozen, there is similar impatience. The French government has divided the country into red and green zones as it gradually lifts its lockdown. But it left Paris in the more restricted red zone, which means it is not allowed to open its parks.

That has enraged the mayor, Anne Hidalgo, who said, “We’ve got to loosen the vise.”

More serious tensions are flaring in Spain, where the left-leaning central government has not eased Madrid’s lockdown because of worries about a resurgence in infections. The Conservative-led city government has lashed out, setting off violent street protests, particularly in affluent neighborhoods where the right-wing party is popular.

At the peak of Spain’s outbreak in late March, more than 300 people a day died in the Madrid region. On Thursday, 19 did. Still, with nearly 9,000 deaths, the capital accounts for roughly a third of the country’s fatalities. And although its death toll has fallen in line with the rest of Spain, Madrid’s statistics arguably still make it the country’s major hot zone.

In Germany, where the capital was never the epicenter of the virus, there has been less friction over the pace of reopening.

Berlin has had a relatively mild outbreak, with 6,552 cases, compared with 26,628 in London. After more than two dozen people were infected in early March at the Trompete club, city officials shut down Berlin’s celebrated nightlife. Restaurants were allowed to reopen their terraces and offer limited service indoors, but there is no sign of when clubs might be allowed to reopen, or how.

While Berlin has had a slight uptick in infections since the reopening, its numbers remain well below those in the southern states of Bavaria and Baden-Württemberg, where skiers returning from South Tyrol and Austria brought the virus back in the late winter.

What pressure there was to reopen came from the western state of North Rhine-Westphalia, which was also among the hardest hit in Germany. The governor, Armin Laschet, urged Chancellor Angela Merkel to “weigh up again how great the risk of pure infections is and what other social, human, economic damage you will cause in society if you keep everything closed.”

Italy, on the other hand, has been fractured by divisions over how to emerge from the lockdown. The disputes have pitted Rome against the hard-hit northern regions of Lombardy and Veneto, but also Campania and Calabria in the south, which all but refused to follow national guidelines.

In Milan, the capital of Lombardy, the government’s phased lifting of the lockdown is drawing deeply mixed emotions. The city, which once reeled under an influx of patients, reported only eight new coronavirus cases on May 20. But officials worry about the risks of reopening shops, restaurants and bars, where Milan residents quickly gathered in groups to drink their beloved aperitivo.

Rome has been luckier, according to epidemiologists.

The city registered the first coronavirus cases in Italy: Chinese tourists from Wuhan, where the virus originated, and an Italian researcher returning from Wuhan. This allowed the Lazio region, where Rome is located, to activate a regionwide system of contact tracing that it used in later cases.

Rome has recorded 2,936 cases and 305 deaths, but it passed a peak the week of April 10, and the declining numbers are contributing to a sense of complacency.

“The virus is still circulating; we haven’t beaten it,” said Alessio D’Amato, Lazio’s counselor for health. “We’re a population that’s used to being together, having active social lives, and as the summer advances it’s more difficult.”

Reporting was contributed by Andrew Testa from London; Adam Nossiter and Aurelien Breeden from Paris; Raphael Minder from Madrid; Melissa Eddy from Berlin; and Elisabetta Povoledo and Emma Bubola from Rome.